In vacuum evaporating deposition, the surface deformation of the optical elements was primarily affected by the substrate stress redistribution including the gravitational stress and the residual stress before and after deposition. A model was built to analyze the effects of substrate stress, the results proved that an interaction stress in the substrate-film interface induced by the gravitational stress in the substrate in the vacuum evaporating deposition produced very little deformation of the substrate. Therefore, the irregular deformation of the optical element induced in vacuum evaporating deposition was determined by the residual stress of the substrate mostly. The experimental results show that the irregular deformation of the substrate caused by the residual stress can be eliminated by fine annealing the substrate before being polished.